SOIL ORGANISMS Volume 81 (3) 2009 pp. 519–530 ISSN: 1864 - 6417 Ectonocryptoides sandrops – a new scolopendromorph centipede from Belize Arkady A. Schileyko Zoological Museum of Moscow State Lomonosov University, Bolshaja Nikitskaja Str.6, 103009, Moscow, Russia; e-mail: [email protected] Abs tract A new representative of the rare subfamily Ectonocryptopinae (Scolopocryptopidae) is described from western Belize as Ectonocryptoides sandrops sp. nov. Both previously known representatives of this subfamily ( Ectonocryptops kraepelini Crabill, 1977 and Ectonocryptiodes quadrimeropus Shelley & Mercurio, 2005) and the new species have been compared and the taxonomic status of the latter has been analysed. Keywords: Ectonocryptopinae, new species, Belize 1. Introduction Some years ago, working on exotic Scolopendromorpha from a collection of Prof. Alessandro Minelli I found one very small (ca 11–12 mm long) scolopendromorph centipede (Fig. 1). It had been collected by Francesco Barbieri in Mountain Pine Ridge of Western Belize (Fig. 2). With 23 pedal segments this blind centipede clearly belongs to the family Scolopocryptopidae Pocock, 1896. According to the very special structure of the terminal legs I have identified this animal as a new species of the very rare subfamily Ectonocryptopinae Shelley & Mercurio, 2005. The structure of the terminal legs (= legs of the ultimate body segment) is of considerable taxonomic importance in the order Scolopendromorpha. Commonly the terminal leg consists of 5 podomeres (prefemur, femur, tibia, tarsus 1, tarsus 2) and pretarsus. The first four podomeres are always present, when tarsus 2 and the pretarsus may both be absent. The terminal podomeres are the most transformable ones. There are six principle (or basic) types of terminal legs among scolopendromorph centipedes: 1) ‘common’ shape (the most similar to the locomotory legs), which is the least specialised (Fig. 3a). 2) ‘Pincer’-shaped (Fig. 3b), adapted for capturing prey (so they are a kind of functional forcipules) with the podomeres shortened, strongly enlarged (triangular in cross-section) and robust. In some genera ( Theatops Newport, 1844; Plutonium Cavanna, 1881; Scolopendropsis Brandt, 1841 etc.) the ‘pincer’-shaped terminal legs are genus- specific, correlating with a strongly enlarged ultimate segment. Such an enlargement may be due to the presence of enlarged muscles, which are necessary to manipulate these appendages 520 Arkady A. Schileyko as functional forcipules. But in the genus Cormocephalus Newport, 1844 there are some species ( C. bonaerius Attems, 1928; C. andinus Kraepelin, 1903 etc.), which demonstrate (evidently, as a result of convergence) the similar shape of terminal legs (vs the majority of the species, which have terminal legs of ‘common’ shape). However, the ultimate segment is never enlarged in these species (Fig. 3c) and this character here is species-specific. 3) ‘Pocket- knife’-shaped (or ‘clasping apparatus’ sensu Shelley & Mercurio 2005), also adapted for capturing prey (Fig. 3d). Fig. 1 Ectonocryptoides sandrops sp. nov. General view. Fig. 2 The known localities of Ectonocryptops kraepelini (triangle), Ectonocryptoides quadrimeropus (dot) and Ectonocryptoides sandrops (asterisk). After Shelley & Mercurio 2005. Ectonocryptoides sandrops sp. nov. from Belize 521 Fig. 3a–d Terminal legs of: a: Scolopendra sp. of ‘common’ shape; b: Theatops spinicaudus (Wood, 1862), ‘pincer’-shaped terminal legs; c: Cormocephalus westwoodi anceps Porat, 1871, ‘pincer’-shaped terminal legs; d: Cryptops sp., ‘pocket-knife’-shaped terminal legs. The terminal legs of these three types have a well-developed pretarsus, whereas the following types have no pretarsus at all. The types are as follow: 4) ‘lasso’-shaped in Newportia Gervais, 1847 and Tidops Chamberlin, 1915 (Fig. 3e), with tarsus 2 divided in very numerous (7 to 40) number of more or less separated secondary articles forming a kind of functional antenna (one of the most specialised shapes). 5) ‘Leaf’-shaped in Alipes Imhoff, 1854 (Fig. 3f), the most specialised (the least similar to the primary condition), these are stridulatory organs, perhaps to frighten potential mammal predators (Skovmand & Enghoff 1980). 6) ‘Ectono’-type in Ectonocryptopinae (Fig. 3g), – enlarged, subclavate, with the inflated distal podomeres; Shelley & Mercurio (2005) have suggested for this type a ‘possible sensory function’. 522 Arkady A. Schileyko Fig. 3e–g Terminal legs of: e: Newportia adisi Schileyko & Minelli, 1998, ‘lasso’-shaped terminal legs; f: Alipes grandidieri (Lucas, 1864), ‘leaf’-shaped terminal legs; g: Ectonocryptoides sandrops sp. nov., left terminal leg and caudal body end, dorsally. The structure of terminal legs is characteristic at the subfamily level in two families – Scolopocryptopidae and Cryptopidae. In other Scolopendromorpha (i.e., in family Scolopendridae) this character is mainly genus-specific but in a few genera (for instance in Cormocephalus s. str.) it may vary within one genus, being species-specific (see above). The terminal legs of ‘ectono’-type are the rarest, being known solely in five specimens, which represent the subfamily Ectonocryptopinae. The first member of this taxon has been described in 1977 by Crabill, who established the monotypic genus Ectonocryptops for a single specimen from Colima in Mexico (Fig. 2). According to the original description, Ectonocryptops kraepelini has a terminal tarsus consisting of two podomeres with ‘ultimate second tarsus subclavate…’. Unfortunately, there are no illustrations in the original description, therefore Shelley & Mercurio (2005) note: ‘… and it is difficult for even a specialist to visualize a new form solely from a written characterization’. Crabill (1977) had placed his new genus in the Cryptopidae without mention of a subfamily. In 2005 Shelley & Mercurio described the monotypic genus Ectonocryptoides . The type species – E. quadrimeropus (orig. designation) – was described on the basis of two specimens from Jalisco close to Colima (Fig. 2). We read in the original description: ‘The ultimate 2nd tarsi are clearly lost in these centipedes, a fundamental difference from E. kraepelini that, for Ectonocryptoides sandrops sp. nov. from Belize 523 consistency within the Scolopocryptopidae and Scolopendromorpha as a whole, warrants generic-level recognition’. In the same paper the authors established for two these genera a new subfamily Ectonocryptopinae. The third specimen of E. quadrimeropus from Tehuacán (Puebla state, central Mexico; Fig. 2), was recently discovered by Shelley ‘among the millipede holdings at the American Museum of Natural History’ (Shelley 2009). However, the formerly missing holotype of Ectonocryptops kraepelini has been recently found and Shelley & Mercurio (2008) redescribed it with drawings. The terminal legs of this animal are of ‘ectono’-type (see Figs 5–6 in Shelley & Mercurio 2008), differing from those of both Ectonocryptoides quadrimeropus (see Figs 12–16 in Shelley & Mercurio 2005) and the new Belize species (Figs 3g, 8–10) in the much longer tibia and the presence of a small, globose tarsus 2. Unfortunately the condition of this holotype did not allow confirmation of Crabill’s (1977) information about absence of sternal paramedial sutures and the number of spiracles in E. kraepelini (11 pairs, according to the original description). Tab. 1 Comparative table for Ectonocryptops kraepelini , Ectonocryptoides quadrimeropus and E. sandrops sp. nov. Ectonocryptops Ectonocryptoides Ectonocryptoides kraepelini quadrimeropus sandrops spiracles at 7th segment present ? present antennomeres 17 17 17 forcipular appendages no no no paramedian sutures of semicomplete semicomplete complete tergum 1 lateral margination at terga 2(3)–23 tergum 23 terga 2(3)–23 sternal sutures absent absent(?) lateral + margination ‘1 lateral spine coxopleural process with ‘2 adjacent setae’ 1–2 spine-like setae apiece’ coxopleural pores about 20 present about 20 tarsus of locomotory legs bipartite monopartite monopartite spurs at locomotory legs absent absent absent Terminal legs: ventral spinous processes 3 3 3 of prefemur ventral spinous processes 2 2 2 of femur additional small spines at absent present absent femur and prefemur length of tarsus 1 < tibia > tibia > tibia tarsus 2 present absent absent pretarsus absent absent present (rudimentary) 524 Arkady A. Schileyko 2. Comparison of the members of Ectonocryptopinae and the taxonomic status of the new Belizean species The diagnostic characters of the new form have been compared with those of two known ectonocryptopines (Tab. 1). The comparative table is incomplete because the known specimens of this subfamily are few in number, small, delicate and mainly in bad condition. It is evident, however, that the new animal is at least a new species, which is closer to Ectonocryptoides quadrimeropus (rather than to Ectonocryptops kraepelini ) because of absence of terminal tarsus 2 – the main diagnostic character of Ectonocryptoides (according to Shelley & Mercurio 2008). Fig. 4 a–c Ectonocryptoides sandrops sp. nov.: a: head + tergum 1, dorsally; Ps: paramedian sutures; Ts: transverse suture; b: tarsus 1 of right terminal leg, medially; Pt: pretarsus; c: head + sterna 1–3, ventrally; Ls: lateral sutures + margination. Ectonocryptoides sandrops sp. nov. from Belize 525 Figs 5–7 5: Newportia adisi Schileyko & Minelli, 1998: Sterna 18–20, ventrally; Ls lateral sutures; 6: Ectonocryptoides sandrops sp. nov.: forcipular segment + tergum 1, ventrally; 7: E. sandrops